Periodic Acid–Schiff-positive Component of the Medullary Bone of the Laying Domestic Fowl

Abstract

INVESTIGATION of avian medullary bone in this laboratory led to the observation of a substance therein which gave a very strong positive reaction with the periodic acid–Schiff technique. In some instances this took the form of branching homogeneous strands or fibrils of irregular thickness distributed in a less-strong periodic acid–Schiff-positive matrix; in other instances it was more dispersed and less distinctly fibrillar. Variation in the amount of this substance was also noted in different stages of the egg-laying cycle and, as a loss of chondroitin sulphate from the cartilage is known to precedo endochondral bone formation, an attempt was made to determine the nature of the periodic acid–Schiff-positive substance in avian bone and to correlate the variations in appearance and amount with the alternate absorption and deposition known to occur in this bone during the egg-laying cycle¹.